You Can’t Convince an Idiot
You can’t convince an idiot of anything. If you think someone is an idiot, two things will will work against you as you argue with them. First off, they’ll know how you feel and they’ll think you’re an idiot for thinking they are an idiot. (And maybe you’re smarter than 90% of the population but that doesn’t really make all of them idiots.) More importantly, you’ll be framing your arguments for idiots, not for the person standing in front of you.
"If I were you, I’d make the same decision you did."
The way I see it, if I were you, and had been born with the same gifts, lived the same life, had the same values, then at any given moment I’d make the same decision you did. So the fact that you made the "wrong" decision, means that you are missing some piece of information, some story, some anecdote that would let you see the problem the same way I do. Maybe you really are an idiot, and I need to dumb down my reasoning – but chances are you are a relatively smart person and you have good reasons for the choices you’ve made whether it’s voting for Obama or supporting the Iraq war. To change your mind, I have to respect who you are, understand that if I were like you, I’d feel the same way, and then figure out what piece of information or what story I can tell you to make you a little more like me.
Most people try to convince people by stating their side of the argument over and over, but what you really need to do is find out what they are missing (or what they’ve experienced) that makes them see the world that way and give them more information, preferably a new experience or a new story. Once their experiences match yours, they’ll be more likely to make the same decisions you make.